shanghai is a center of research, development and higher education. most new chinese cars are now made here. migrants from the interior flock to make new lives here. but the surge in growth is relatively recent. until 1991, shanghai was stymied. why was it held back, and how did it boom? some of the answers may be found in china's historical geography, which colors its outlook toward foreigners. for centuries, the threat came over land, from the north and west. mongols and manchus frequently raided, and often ruled, chinese society. more recently, the invaders came by sea. following a victory in the opium wars, the british won concessions in several chinese ports, including shanghai in 1843. shanghai reached t zenith of its colonial power in the early 20th century. the outside presence can still be seen. the old foreign trading houses occupy prime positions on the waterfront strip called "the bund," a reference to german authority. ( machine gun fire ) ( explosion ) narrator: in 1937, japan invaded shanghai. its status as a trading city was virtually